SQLite

/*
** 2004 April 6
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** $Id: btree.c,v 1.182 2004/08/14 19:20:10 drh Exp $
**
** This file implements a external (disk-based) database using BTrees.
** For a detailed discussion of BTrees, refer to
**
**     Donald E. Knuth, THE ART OF COMPUTER PROGRAMMING, Volume 3:
**     "Sorting And Searching", pages 473-480. Addison-Wesley
**     Publishing Company, Reading, Massachusetts.

  unsigned char *pP1;

  assert( idx>=0 && idx<=15 );
  rc = sqlite3pager_get(pBt->pPager, 1, (void**)&pP1);
  if( rc ) return rc;
  *pMeta = get4byte(&pP1[36 + idx*4]);
  sqlite3pager_unref(pP1);

  /* The current implementation is unable to handle writes to an autovacuumed
  ** database.  So make such a database readonly. */
  if( idx==4 && *pMeta>0 ) pBt->readOnly = 1;

  return SQLITE_OK;
}

/*
** Write meta-information back into the database.  Meta[0] is
** read-only and may not be written.
*/

**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.251 2004/08/14 19:20:10 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** The following constant value is used by the SQLITE_BIGENDIAN and

  /* Get the database meta information.
  **
  ** Meta values are as follows:
  **    meta[0]   Schema cookie.  Changes with each schema change.
  **    meta[1]   File format of schema layer.
  **    meta[2]   Size of the page cache.
  **    meta[3]   Use freelist if 0.  Autovacuum if greater than zero.
  **    meta[4]   Db text encoding. 1:UTF-8 3:UTF-16 LE 4:UTF-16 BE
  **    meta[5]
  **    meta[6]   
  **    meta[7]
  **    meta[8]
  **    meta[9]
  **

# 2001 September 15
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script is btree database backend
#
# $Id: btree.test,v 1.30 2004/08/14 19:20:10 drh Exp $


set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Basic functionality.  Open and close a database.
#

    btree_update_meta $::b1 0 1 2 3 4 5 6 7 8 9
  } msg]
  lappend rc $msg
} {1 SQLITE_ERROR}
do_test btree-5.3 {
  btree_begin_transaction $::b1
  set rc [catch {
    btree_update_meta $::b1 0 1 2 3 0 5 6 7 8 9
  } msg]
  lappend rc $msg
} {0 {}}
do_test btree-5.4 {
  btree_get_meta $::b1
} {0 1 2 3 0 5 6 7 8 9}
do_test btree-5.5 {
  btree_close_cursor $::c1
  btree_rollback $::b1
  btree_get_meta $::b1
} {0 0 0 0 0 0 0 0 0 0}
do_test btree-5.6 {
  btree_begin_transaction $::b1
  btree_update_meta $::b1 0 10 20 30 0 50 60 70 80 90
  btree_commit $::b1
  btree_get_meta $::b1
} {0 10 20 30 0 50 60 70 80 90}

proc select_all {cursor} {
  set r {}
  btree_first $cursor
  while {![btree_eof $cursor]} {
    set key [btree_key $cursor]
    lappend r $key